VDO Pressure Senders are designed to work with VDO gauges only. They're matched to gauges according to the maximum reading on dial faces. Unless otherwise noted, senders are 10-180 ohms and standard ground (sender case to common ground). Floating ground indicates the presence of an additional terminal to be used as a ground (isolated terminal to common ground). VDO senders have tapered threads: DO NOT use PTFE tape or pipe sealant, as this will interfere with grounding.